The regulation of network industries has undergone profound transformation in the past twenty years. The regulated industry is no longer the same, being exposed to new competitive dynamics having revolutionized their industrial framework, technology and interactions with users. There also have been fundamental changes in what regulation is feasible. In an “information society” a model devised in the 19th century to set prices for monopoly infrastructures such as bridges, roads and railways no longer captures the essential: the interactive dynamics created by technologies, uses, and markets.